CBS HealthWatch

LOS ANGELES (CBS) ― Lisa Sigell sat down with dermatologist Wendy Hoffman to discuss the sun's affect on skin and what we can do to protect ourselves from harmful rays.

Lisa: What is Ultra Violet light?

Dr. Hoffman: Ultra Violet is radiation that comes from the sun that can cause damage to the skin. It comes in the UVA and UVB range that can cause damage to the skin.

Lisa: How do you protect yourself from Ultra Violet light?

Dr. Hoffman: You can protect yourself with sunscreen and protective clothing, like hats and long sleeve shirts, with a tight weave.

Lisa: What do you tell your patients about antioxidants?

Dr. Hoffman: Anti-oxidants can protect the skin by neutralizing free radicals that comes by ultra violet light effects on the skin.

Lisa: How important are anti-oxidants?

Dr. Hoffman: Antioxidants are very important and they can really both protect the skin from future ultra violet damage as well as help with present photo damage, and really repair the skin.

Lisa: What is SPF?

Dr. Hoffman: So SPF is Sun Protection Factor and is measured by how much protection you get from UVB only it actually doesn't measure UVA at all. The easy way to look SPF is if it's an SPF 15 you can stay out in the sun fifteen times longer than you would otherwise without burning.

Lisa: So what level of SPF do you need?

Dr. Hoffman: So people with very fair skin, those who burn really easily, I certainly always recommend a high SPF over 30, even up in the fifty, sixty, there's sunscreens up to eighty-five. Because a lot of people don't put on a lot of sunscreen, and we really want to protect them, make sure they use the right SPF and the right amount of sunscreen.

Lisa: Which brings us to the question…how much sunscreen do you need and how often should you reapply it?

Dr. Hoffman: So you need a shot glass full of sunscreen that will cover your entire body once, so it's a good amount of sunscreen, you want a really nice layer all over the areas that are exposed to the sun.

Lisa: Do you always know when you have sun damage? Can you see it?

Dr. Hoffman: You can't really see it in the very beginning, bug after the age of 25, 30, 40, you definitely start to see the sings of sun damage which are, brown spots, wrinkling, rough skin, and even skin cancers.

Lisa: Can you repair your skin after you've had a lot of sun damage?

Dr. Hoffman: You can't 100 percent turn back the clock but you can protect the skin using sunscreen, anti-oxidants, retinods, and certainly some laser procedures as well.

Lisa: What do you tell your patients about going in the sun?

Dr. Hoffman: I tell them not to go in the sun, but if they have to go in the sun, I tell them to do it wisely, and to protect themselves. Not to go out in the sun between ten and two if you can help it, and if you are going out in the sun use a high SPF sunscreen. Make sure its broad spectrum, water resistant, and use a broad rim hat and protective clothing.

Lisa: What is the worst time of day to go out in the sun?

Dr. Hoffman: So you don't want to go out in the sun between ten and two, that's really when the UV rays are the strongest.

Lisa: So how do you protect yourself from UV exposure?

Dr. Hoffman: We know that the sun's most intense rays are between 10 a.m. and 2 p.m., so the best thing to do is stay out of the sun, between ten and two. In addition you can wear protective clothing, broad rim hats and sun screen.

Lisa: What are sunscreens?

Dr. Hoffman: Sun screens are products that protect your skin from ultra violet light, from ultra violet light, they come in a variety of strengths, from the very weakest being two, which doesn't really do anything, its more of a cosmetic thing to let you tan, and then really protective sun screens form 15, 30, and up even up to 85.

Lisa: How do sunscreens work?

Dr. Hoffman: Sunscreens have many chemicals in them, some of them absorb the ultra violet light, some of them scatter it and reflect it.

Lisa: What type of sunscreen they should use? Are there different types for different skin types?

Dr. Hoffman: Absolutely…what you have to do is figure out where you're going, what you're doing, and what kind of skin you have. So if you're applying sunscreen to a hairy area, you might want to use a gel or a spray. If you have very dry skin, you might want to use a cream or a lotion. I often will use the stick sunscreen on my kids, because they hate it when it goes into their eyes. So a lot of times you will have to use different types of sunscreens for different body parts. Bald men they should always be wearing a hat, or you can always use the spray sunscreen that seems to work well for them.

Lisa: When you're using sunscreen for children, what do you need to know?

Dr. Hoffman: Children are very susceptible to ultra violet damage and to sun burn, so you really have to protect them, they are going to be so anxious to run out in the ocean the minute you put on the sunscreen, but the reality is that you really have to put on the sunscreen thirty minutes before going outside so it has time to absorb into the skin. It also comes off pretty easily in the sun, with sweating and with swimming, so you want to make sure that you are reapplying often, really as often as maybe once an hour, once every two hours, if you or your children are sweating a lot or in the water. What you're looking for is sunscreen that has broad spectrum, that means covering the UVA and the UVB spectrum, as well as water resistant, and a high SPF, so an SPF of over 30 at least. The bottom line is that we don't really put on a lot of sunscreen, and that's the problem, is that we just lather it on, here and there, and it ends up either wiping off, or you think you're using a thirty, but the amount you've put on is closer to a four. And that's when you get all the sunburn and all the sun damage. You want to make sure that you're using enough of the sunscreen. They say that a shot glass worth to cover your whole body, you really want, a nice thin film over the entire surface of your skin to have adequate protection.

Lisa: Is SPF an indication of how long you can stay in the sun?

Dr. Hoffman: SPF is a predictor, but nothing is perfect. Because if you put on not enough sunscreen, you're not going to be able to be out in the sun out long like it says on the bottle, for example. And if you're sweating profusely it's going to wear off, or if you towel off, after you've gone for a swim, you probably don't even have any sunscreen left. So it really depends on your activity level, how much you're sweating, if you're swimming, and certainly if you've put on an adequate amount of sunscreen.

Lisa: As a dermatologist, what are the tips you tell people about sunscreen?

Dr. Hoffman: Make sure you put enough on, make sure you put it on thirty minutes before you go out, use at least an SPF fifteen; I usually say an SPF fifteen on a daily basis, and definitely thirty or higher when your out in the sun, sports, recreation, and certainly if your out on vacation at a very sunny place. You want broad spectrum, water resistant, and you want to use enough to protect you.

Lisa: And also protective clothing?

Dr. Hoffman: exactly, protective clothing, broad hats. So when we wear a typical baseball hats, your ears are always sticking out, and I do a lot of skin cancer surgery, and I can tell you I see a lot of sun damage and skin cancers on the tips of the ears, because people never put sunscreen there. So don't forget to put those delicate, sensitive areas.

Lisa: Can you tell by looking at your skin if you have spent too much time in the sun?

Dr. Hoffman: Well, when you're really young you can't, but as you get older you start seeing the changes, from sun, which would be brown spots, model pigmentation, and certainly wrinkles and eventually skin cancers.

Lisa: Is it safer on a cloudy day?

Dr. Hoffman: Well on cloudy days, at about 80 percent of the ultra violet rays can actually penetrate through those clouds, so you still have to protect yourself on cloudy days.

Lisa: Are there ways that you can be exposed to harmful UV other than direct sunlight?

Dr. Hoffman: So tanning beds are the perfect example, to be exposed to ultra violet light, and it does cause skin cancers and sun damage, wrinkling and brown spots, so we do not advice in going to tanning beds, they are not safe.

Lisa: Is a tanning bed safer than sunlight?

Dr. Hoffman: So tanning beds are not safer than sunlight, in fact, sometimes the tanning lights are even a higher ultra violet radiation than the natural ambient sunlight. They did a study recently that showed people who went to tanning bed regularly had an increased risk of skin cancer by seventy five percent.

Lisa: What can reduce the effectiveness of sunscreens?

Dr. Hoffman: If you put your sunscreen on, right when you go out in the sun, it does not have time to absorb, so you really, want to put the sunscreen on thirty minutes before. In addition you don't want to towel it off or put the sunscreen on and slip your shirt on over because it will wipe off. In addition heavy sweating, swimming, even insect repellents can decrease the effectiveness of sunscreen.

Lisa: Are all the sunscreen the same? And if they are not how are they different?

Dr. Hoffman: Sunscreens certainly come in different SPF's, so I prefer using the higher SPF's certainly over thirty, because in case your not using enough, at least you'll get a higher SPF and protect your skin. They also come in different vehicles, they come in cream, lotions, gels, and sticks, and so you want to pick the vehicle or the product that works best for your skin, if you have a really oily skin you might want to use a light lotion, if you have really dry skin, you might want to use a creamy sunscreen, and it'll go on your skin better.

Lisa: So what should you look for on a label?

Dr. Hoffman: So this is what I tell my patients, make sure your using a broad spectrum sunscreen that covers the UVA and UVB wavelength, in addition use one that is at least SPF 30 or more, again for every day I want patients to use SPF 15 under the make up on a daily basis. But if you're going somewhere sunny or doing an outdoor activity, I want you to use at least an SPF 30.

Lisa: What time of day should you avoid the sun?

Dr. Hoffman: Well, classically between ten am and two pm, are the most intense times of sun, ultra violet radiation.

Lisa: What happens when you've been burned?

Dr. Hoffman: If you've been burned the damage is already done, I cant prevent the blistering from happening, but I can definitely make you more comfortable, and make it less of a traumatic event. So I tell patients to take ibuprofein, have them use a little hydro cortisone cream to decrease some of the inflammation, and aloe is actually quite soothing to the burns as well.

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